x86: Don't generate vzeroupper if caller passes AVX/AVX512 registers

There is no need to generate vzeroupper if caller passes arguments in
AVX/AVX512 registers.

Tested on i686 and x86-64 with and without --with-arch=native.

gcc/

	PR target/88717
	* config/i386/i386.c (ix86_avx_u128_mode_exit): Call
	ix86_avx_u128_mode_entry.

gcc/testsuite/

	PR target/88717
	* gcc.target/i386/pr88717.c: New test.

From-SVN: r267732

gcc/ChangeLog

+2019-01-08  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR target/88717
+	* config/i386/i386.c (ix86_avx_u128_mode_exit): Call
+	ix86_avx_u128_mode_entry.
+
 2019-01-08  Martin Liska  <mliska@suse.cz>
 
 	PR tree-optimization/88753

gcc/config/i386/i386.c

@@ -19137,7 +19137,10 @@ ix86_avx_u128_mode_exit (void)
   if (reg && ix86_check_avx_upper_register (reg))
     return AVX_U128_DIRTY;
 
-  return AVX_U128_CLEAN;
+  /* Exit mode is set to AVX_U128_DIRTY if there are 256bit or 512bit
+     modes used in function arguments, otherwise return AVX_U128_CLEAN.
+   */
+  return ix86_avx_u128_mode_entry ();
 }
 
 /* Return a mode that ENTITY is assumed to be

gcc/testsuite/ChangeLog

+2019-01-08  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR target/88717
+	* gcc.target/i386/pr88717.c: New test.
+
 2019-01-08  Marek Polacek  <polacek@redhat.com>
 
 	PR c++/88548 - this accepted in static member functions.

gcc/testsuite/gcc.target/i386/pr88717.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -mavx512f -mvzeroupper" } */
+
+#include <immintrin.h>
+
+__m128
+foo1 (__m256 x)
+{
+  return _mm256_castps256_ps128 (x);
+}
+
+void
+foo2 (float *p, __m256 x)
+{
+  *p = ((__v8sf)x)[0];
+}
+
+void
+foo3 (float *p, __m512 x)
+{
+  *p = ((__v16sf)x)[0];
+}
+
+/* { dg-final { scan-assembler-not "vzeroupper" } } */